ABSTRACT
Herpes simplex keratitis(HSK), caused by the infection of herpes simplex virus type Ⅰ(HSV-1)in cornea, is a global blinding corneal disease. After the primary infection in ocular surface, HSV-1 is transported into trigeminal ganglion and establishes the life-lasting latency, and it results in recurrent keratopathy. In the process of studying the latent mechanism of HSV, it has been gradually recognized that both the virus itself and the host response regulate the latent process of HSV. In recent years, a large number of research results have been obtained on the molecular mechanisms of invasion, immunity, latency and recurrence of neurotropic viruses, which provide new ideas for the prevention and treatment of HSK. In the present review, the recent progress of HSV latency mechanism in trigeminal ganglion after the primary infection in corneal surface was introduced, and the unsolved basic and clinical problems in HSK were discussed.
ABSTRACT
Background Human retinal pigment epithelial (RPE) cell transplantation treating retinal degenerative diseases is a researching topic,and the source of human RPE cells is a key problem.Many biological carriers can be used for the preparation of RPE cell layer.However,some advantages,such as cytotoxicity,lack of stability and immunologic reaction etc.are still existed.To study an ideal biological carrier is very important.Objective This experimental was to determine the effects of amniotic membrane on the proliferation and differentiation of human RPE cells and the possibility as a scaffold for RPE cell transplantation.Methods ARPE19 cell line cells were cultured and passaged in DMEM/F12 medium with 10％ fetal bovine serum,and 8-12generation of cells were used.The cells were divided into two groups.One group of cells were incubated on the denuded amniotic membrane,and the other group of cells were cultured in the medium (control group).MTT was performed to detect the A492 value of RPE cells for the evaluation of cell proliferation ability 24,48,72,96 hours after culture.Cell morphology was compared by histopathological examination 3 weeks after culture.The mRNA expression of pigment epithelium-derived factor (PEDF),N-cadherin,β-catenin and cell connection related proteins in the cells of both groups were assayed using reverse transcription polymerase chain reaction (RT-PCR).Ultrastructure of the cells was observed under the transmission and scan electronic microscope 3 weeks after culture.Results The number of ARPE-19 cells cultured on denuded amniotic membrane was decreased significantly in comparison with the normal culture plate(F=41.760,P =0.000).Histopatholy also showed that the cell density on amniotic membrane was lower than of normal cells on plate surface.Moreover,the expression level of claudin 1 mRNA,N-cadherin mRNA and PEDF mRNA were significantly up-regulated in denuded amniotic membrane group in comparison with control group (t=15.828,P=0.000 ;t=6.839,P=0.002 ;t=14.667,P=0.000),but the expression of Connexin 43 mRNA was down-regulated in denuded amniotic membrane group compared with control group(t=3.358,P=0.024).Ultrastructural examination revealed that ARPE-19 cells cultured on amniotic membrane exhibited a polygonal epithelial phenotype with cilium on the apical side,however,the cells cultured on normal culture plate displayed fusiform shape and uneven thickness.Conclusions Amniotic membrane plays a promoting effect on the differentiation of ARPE-19 cells and a inhibitory effect on the proliferation of ARPE-19 cells,suggesting that amniotic membrane might be an useful scaffold for the preparation of functionally mature RPE cells for clinical transplantation.
ABSTRACT
Recent years,progress has been made on the basic researches and clinical applications of ocular surface reconstruction with autologous or allogeneic limbal stem cells,oral mucosa epithelium and ex vivo cultured limbal stem cells.However,there are several issues,including the successful treatment for severe ocular damage,longterm follow-up and evaluation of clinical outcome,and the in vivo tracking of donor stem cells,remained to have definitive conclusions.Future studies should address the questions and challenges based on the basic research of limbal stem cell deficiency and standardized evaluation of clinical outcome.
ABSTRACT
AIM: To detect the differentiation effects of retinal cells or extracts on bone marrow-derived mesenchymal stem cells (BMSC).METHODS: Human fetal BMSC were previously labeled by carboxyfluorescein succinimidyl ester (CFSE), and co-cultured with retinal pigment epithelial （RPE） cells which were pre-treated with ultraviolet irradiation at a ratio of 1∶1 to induce the differentiation of BMSC for up to 14 days. In some assays, a retinal extract of bovine retinal extract (BRE) was added to detect the potential effects of retinal component on the differentiation of BMSC. In addition, neuron-specific enolase (NSE), Nestin and Glial fibrillary acidic protein (GFAP) immunostaining were performed to determine the characteristics of BMSC.RESULTS: The results indicated that by co-cultured with RPE cells, fetal BMSC were differentiated into neural-like cells expressing special neuronal markers Nestin, GFAP and NSE. And the expression of these markers was obviously increased by BRE.CONCLUSION: Retina derived cells and extracts can induce the differentiation of BMSC into neural-like cells.
ABSTRACT
Orthotopic liver transplantation has proven to be effective in the treatment of a variety of life-threatening liver diseases, however, the limitations of donated organs available and long-term immunosuppression provided an impetus for developing alternative therapies. Cell replacement strategies have been one major effective approach for overcoming the obstacles of organ transplantation in recent years. The exogenous cells should be able to proliferate and differentiate into mature hepatic cells after grafting. Use of mature hepatocytes is also hampered by limited tissue source and inability to proliferate and maintain the function for a long term in vitro. Embryonic stem cells are immortal and pluripotent and may provide a novel cell source for potential cell therapy. This review summarizes the mechanisms of controlling early liver development and hepatic differentiation of visceral endoderm in embryoid bodies, and provides an overview of diverse differentiation systems in vitro and in vivo that were applied to hepatic research in recent years. Several studies have demonstrated that ES cell-derived hepatocytes can incorporate into liver tissue and function in vivo , but a few of them have shown complete restoration of liver function after transplantation into mice with liver diseases. Further studies should be made to exploit efficient methods and clinical applications of hepatocytes derived from ES cells in the future. In addition to clinical transplantation for treatment of liver diseases, ES cells can provide a valuable tool for drug discovery applications and study on of molecular basis of hepatic differentiation.